1. Field of the Invention
The present invention relates to a vehicle door system, more specifically, to a vehicle door system including a mechanism for preventing one of a pair of doors, which are arranged on a side portion of a vehicle body along the longitudinal direction of a vehicle, from being jammed inside the other door due to the force generated due to a forward collision or the like.
2. Description of the Related Art
With regard to this type of vehicle door system, the following is available (see Japanese Patent Application Publication No. H10-152069 (JP-A-H10-152069), for example). Shown in the vehicle door system is an example of a door-openability securing system that secures the openability of vehicle doors after a collision. In this example, a seesaw member is disposed between a rear end portion of a front door and a center pillar. When a force is applied to the front door at the time of a forward collision, and the front door in turn pushes a front arm portion of the seesaw member, the seesaw member rotates and a rear end portion of the front door is pushed and displaced outwardly in the vehicle width direction by a side arm portion of the seesaw member, whereby the jamming of the front door inside a rear door is prevented.
However, with regard to the example described in JP-A-H10-152069 cited above, it is necessary for the rear end portion of the front door to be pushed and displaced outwardly in the vehicle width direction in order to prevent the jamming of the front door inside the rear door at the time of a forward collision or the like. For this purpose, there are various restrictions as described below, for example.
Specifically, it is necessary for the seesaw member to be rotated in order to push and displace the rear end portion of the front door outwardly in the vehicle width direction, and for this purpose, it is necessary for the front door to be moved toward the rear of the vehicle and push the front arm portion of the seesaw member following a forward collision or the like.
In addition, in order to allow the front door to move toward the rear of the vehicle at the time of a forward collision or the like as mentioned above, it is necessary to reserve a wide space between a terminal edge portion of the front door and a terminal edge portion of the rear door so that the terminal edge portion of the front door and the terminal edge portion of the rear door do not interfere with each other.
Moreover, in order for the rear end portion of the front door to be pushed and displaced outwardly in the vehicle width direction, it is necessary that the pushing force applied by the seesaw member to the front door is greater than the holding force applied by the door lock that makes the front door and the vehicle body fixed to each other.